Duality and quantum-algebra symmetry of the AN−1(1) open spin chain with diagonal boundary fields Original Research Article

We show that the transfer matrix of the AN−1(1) open spin chair with diagonal boundary fields has the symmetry Uq(SU(l)) × Uq(SU(N−l)) × U(1), as well as a “duality” symmetry which maps l ↔ N − l. We exploit these symmetries to compute exact boundary S-matrices in the regime with q real.